Sunday, June 14, 2015

Most boat sinkings happen at the dock. The most common reason is a failed through hull or the attached hose. The nightmares scenario is a failure at sea, with no way to quickly install plug. In fact, during our delivery trip home we experienced a small failure.

The head bulkhead is at top, the holding tank bottom. There is a crash tank, also sealed, in front of the holding tank. It was the speed sending unit, lowermost in the picture, that leaked due to a faulty o-ring.

While not always practical, why not put the through hulls in a bulk headed compartment? On a monohull this could be practical either forward or aft, or by running the bulkhead up the side. You do have to hang down to service valves, and opening them is not very handy (extensions can be fitted), but it is safe. During the homecoming trip we flooded this compartment right to the the water line without ill effect.

Sunday, June 7, 2015

It has long been known that copper and zinc are very bad for fuel stability (gasoline and diesel). The use of these materials is banned by good practice, ASTM standards, fuel producer and engine manufacturer guidance.

Material. Black iron pipe is best suited for diesel fuel lines. Steel or cast iron valves and fittings are preferred.

CAUTION: Copper and zinc, either in the form of plating or as a major alloying component, should not be used withdiesel fuels. Zinc is unstable in the presence of sulfur, particularly if moisture is present in the fuel. The sludge formed by chemical action is extremely harmful to the engine’s internal components.

Diesel Fuel Piping. Diesel fuel lines should be constructed from black iron pipe. Cast iron and aluminum pipe and fittings must not be used because they are porous and can leak fuel. Galvanized fuel lines, fittings, and tanks must not be used because the galvanized coating is attacked by the sulfuric acid that forms when the sulfur in the fuel combines with tank condensate, resulting in debris that can clog fuel pumps and filters. Copper lines should not be used because fuel polymerizes (thickens) in copper tubing during long periods of disuse and can clog fuel injectors. Also, copper lines are less rugged than black iron, and thus more susceptible to damage.

Note: Never use galvanized or copper fuel lines, fittings or fuel tanks. Condensation in the tank and lines combines with the sulfur in the diesel fuel to produce sulfuric acid. The molecular structure of the copper or galvanized lines or tanks reacts with the acid

1.5 gallons of diesel were left for 4 months in a clean closed but vented bucket. The metals samples and water drawn from the atmosphere combined to destroy the fuel. Interesting.

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And yet West Marine and Defender Marine continue to sell brass and copper parts for fuel systems and we continue to buy them! Simply put, they are greedy and we are stupid.

What can we do, short of ripping out plumbing and installing hose, aluminum, and steel?

The best patch is a good corrosion inhibitor (Practical Sailor August 2012 for gasoline, Practical Sailor August 2013 for diesel) that will prevent corrosion (without corrosion the ions will not be present in the fuel) and sequester those that may already be present (from the refining and distribution process, or from the corrosion that has already taken place in your boat). Just a few ppm of free ions will dramatically accelerate fuel degradation.

Shoal Survivor (PDQ 32/34) is For Sale

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Keeping a Cruising Boat for Peanuts--Available in PDF!

As much as I love sailing, putting my daughter through college and funding my 401K are more important. Transitioning from professional engineer to writer has transformed my habit of living efficiently into a passion for spreading funds thin. I like to think of it as a challenge for the imagination—it’s more fun that way.

I’ve written over 100 equipment reviews and engineering articles for popular sailing magazines, all based on laboratory and hands-on testing. I’ve spent 30 years learning how to maintain, fix, and upgrade. I've also spent 35 years as a chemical engineer, and my wife thinks I live in my basement shop.

As a result I’ve become a fair hand most crafts, never get stuck in the field with something I can’t fix, and I've learned to spread money thin, without compromising speed, reliability, or performance. Although I've written on many topics, my wife assures me this is the one I know best. My magnum opus?

About Me

This is my place to share my enthusiasm for the Chesapeake Bay, Delmarva Peninsula, PDQ specific minutia, and sailing in general. As a regular contributor to sailing magazines including Practical Sailor and Good Old Boat (over 100 articles), it provides a place to try out ideas and publish the overflow. Here I can blurt it out half formed ideas, collect comments, and to see what questions my inquiry suggests. If I need to get long winded or philosophical, it’s my space to do so.
After 10 years of kayaking, 25 years of sailing, 30 years of rock and ice climbing, and 35 years as a chemical engineer, I still have much to learn and my life is still one giant science project. My end of the pier is always festooned with test rigs and warning signs. Every research project brings surprises—things I didn’t know, and just as often, things no one knew. And so through books and articles, I share.